One of the most useful tasks an awareness-level rescuer can do to maintain control of a scene is to establish, mark, and maintain the:

Establishing, marking, and maintaining the perimeter is crucial for an awareness-level rescuer to ensure scene control. The perimeter acts as a boundary that defines the area of operation, ensuring that only authorized personnel can access the scene, which helps maintain safety for both rescuers and victims. It helps in the organization of the rescue efforts, reducing the risk of injuries, and keeping bystanders at a safe distance from potential hazards.

Through effective perimeter management, the rescuer can also facilitate communication and the coordination of resources, as this designated area allows the team to operate without distractions and confusion. This is essential for maintaining situational awareness and ensures that the rescue efforts are conducted efficiently and safely. Thus, marking and controlling the perimeter is one of the key tasks that contribute significantly to the overall effectiveness of the rescue operation.